The amount of purchase price allocated to investment properties.

No definition available.

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- Definition

Amount of transaction expenses after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

+ References

No definition available.

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The life, in years, over which the excess investment in equity method investments is amortized.

+ References

No definition available.

+ Details

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- Definition

The number of partner's interest acquired.

+ References

No definition available.

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- Definition

The number of real estate properties in which additional interests were acquired during the period.

+ References

No definition available.

+ Details

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- Definition

This element represents the number of real estate properties that were disposed of during the period.

+ References

No definition available.

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- Definition

Represents the gain recognized upon acquisition of property interests.

+ References

No definition available.

+ Details

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- Definition

Percentage of property interests acquired as of the acquisition date.

+ References

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 30
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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

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- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

+ Details

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- Definition

In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)(2)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2443-110228

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
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- Definition

Amount of increase in real estate investments from acquisitions other than through foreclosure for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28.4)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 10
-Section S99
-Paragraph 6
-Subparagraph (SX 210.5-04.(c) Schedule III)
-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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Balance Type:	debit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

+ References

No definition available.

+ Details

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- Definition

Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

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No definition available.

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Real Estate Acquisitions and Dispositions (Details) $ in Thousands									1 Months Ended	3 Months Ended		6 Months Ended	12 Months Ended
	Jan. 15, 2015 USD ($) property	Sep. 26, 2014 USD ($)	Apr. 10, 2014	Jan. 30, 2014 USD ($) a shares	Jan. 10, 2014 USD ($) property item	Jan. 10, 2014 property item	Aug. 08, 2013 USD ($)	May. 30, 2013 USD ($) ft²	Jan. 31, 2016 USD ($) property	Dec. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) property	Dec. 31, 2014 USD ($) property	Dec. 31, 2013 USD ($) property
Real Estate Acquisitions and Dispositions
Discontinued operations transaction expenses														$ 38,163
Subsequent Event
Real Estate Acquisitions and Dispositions
Gain (loss) on disposition of interest in properties									$ 36,800
Number of properties disposed of during the period \| property									2
McArthurGlen Group
Real Estate Acquisitions and Dispositions
Number of properties in which interest is acquired \| property															5
Hotel
Real Estate Acquisitions and Dispositions
Gain (loss) on disposition of interest in properties		$ 4,500
Office property, Boston, Massachusetts
Real Estate Acquisitions and Dispositions
Gain (loss) on disposition of interest in properties							$ 7,900
Jersey Gardens and University Park Village
Real Estate Acquisitions and Dispositions
Acquisition related transaction costs													$ 4,400
Ownership interests acquired (as a percent)	100.00%
Cash purchase price for acquisition	$ 677,900
Mortgage debt including debt premiums	$ 405,000									$ 17,900			17,900
Investment properties										1,100,000			1,100,000
Lease related intangibles										$ 3,600			3,600
Number of properties in which interest is acquired \| property	2
Jersey Gardens and University Park Village \| Maximum
Real Estate Acquisitions and Dispositions
Life of joint ventures with excess investment										40 years
Arizona Mills
Real Estate Acquisitions and Dispositions
Ownership interests acquired (as a percent)				50.00%
Mortgage debt including debt premiums				$ 166,900
Area of property (in square feet) \| a				39
Consideration paid				$ 145,800
Gain due to acquisition of controlling interest											$ 2,700
Ownership interest after acquisition (as a percent)				100.00%
Arizona Mills \| Operating Partnership
Real Estate Acquisitions and Dispositions
Number of units issued in connection with acquisition of the remaining interest in Arizona Mills \| shares				555,150
Portfolio of ten properties
Real Estate Acquisitions and Dispositions
Consideration paid					$ 114,400
Number of partner's interest acquired \| item					1	1
Number of properties in which interest is acquired \| property					10
Outlet center, Portland OR
Real Estate Acquisitions and Dispositions
Area of property (in square feet) \| ft²								390,000
Property interest acquired (as a percent)								100.00%
Property interest acquired								$ 146,700
Gain on acquisition of property interests								$ 27,300
Partially owned properties
Real Estate Acquisitions and Dispositions
Gain (loss) on disposition of interest in properties															$ 80,200
Consolidated properties \| Portfolio of ten properties
Real Estate Acquisitions and Dispositions
Number of properties in which interest is acquired \| property					7	7
Consolidated properties \| Retail properties
Real Estate Acquisitions and Dispositions
Gain (loss) on disposition														$ 21,800
Number of properties disposed of during the period \| property														3	8
Unconsolidated properties \| Retail properties
Real Estate Acquisitions and Dispositions
Gain (loss) on disposition of interest in properties													$ 43,600
Number of properties disposed of during the period \| property													3		3
Unconsolidated properties \| Lifestyle/Community Centers
Real Estate Acquisitions and Dispositions
Number of properties in which interest is acquired \| property															3
Number of properties disposed of during the period \| property															3
Ashford Designer Outlets \| European Joint Venture
Real Estate Acquisitions and Dispositions
Joint venture ownership percentage before transaction			22.50%
Joint venture ownership percentage after transactions			45.00%
Spinoff \| Strip Center Business and Small Malls
Real Estate Acquisitions and Dispositions
Discontinued operations transaction expenses												$ 38,200